Follow-up to the render-reliability batch (#1841/#1842/#1843). Threads two capture-reliability counters through the existing observability → CLI-telemetry pipeline (no new PostHog wiring) so #1842's hardening is measurable on dashboard 1783183:
- transient-retry burn (CaptureAttemptSummary.reason gains "transient-retry"; counted into RenderCaptureObservability.transientRetries on BOTH the recovered and the still-failed paths via a shared helper).
- OOM classification (memoryExhaustionDetected set when describeMemoryExhaustion classifies the failure).
Surfaced as capture_transient_retries + capture_memory_exhaustion_detected render-event props. Tests cover the attempt tagging and the payload mapping.
Further follow-up (different subsystems): encoder-frame-0-exit signal, and P1-3 pre-flight-rejection / P1-4 cli_env_check counters.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
